Table 3.

Multivariate Voxel Forecast models with patient-level and voxel-level predictors for mid-RT PET SUV

Patient-level only model PPatient- and voxel-level model P + V
Patient/tumor variableβ (95% CI)Pbβ (95% CI)P
Stage IIIB (vs. other)22.9 (−9.0, 65.8)0.1723.6 (−7.6, 65.6)0.15
Primary SUVmeana, per 50% increase21.5 (9.6, 34.6)0.001−9.8 (−19.4, 0.9)0.069
Mean dose between pre-RT and mid-RT PET, per 1-Gy increase−4.6 (−10.3, 1.5)0.13−4.0 (−9.5, 1.8)0.17
Voxel variable
 Voxel pre-RT SUVa, per 50% increase34.8 (29.2, 40.7)<0.001
 Voxel RT dose, per 1-Gy increase−0.3 (−0.8, 0.2)0.28
 Voxel distance from tumor centroid, per 1-cm increase−1.1 (−3.3, 1.1)0.30
  • aThe predictor was log-transformed prior to inclusion in the model to reduce right skewness.

  • bBoldfaced values indicate statistical significance (P < 0.05).